Power-operated hook



April 20, 1954 F. K. MITTRY, JR

POWER-OPERATED HOOK Filed Aug. 6, 1949 l I l I .A a 54l 54 INVENTOR.

FOO/70 16. 44/7789, J2.

Patented Apr. 20, 1954 UNITED STATES PATENT OFFICE 8 Claims.

This invention relates to power operated hooks, and more particularly topower operated hooks used in conjunction with cranes or other hoistingdevices for grasping heavy loads such as concret laden dump buckets,baled scrap iron, etc.

of the objects of my invention is to provide a power operated hook, thejaws of which are capable of lifting great Weights without danger of theload causing the jaws to open.

Another object of my invention is to provide a power operated hookhaving a fast-acting, remotely-controlled pneumatic power unit foropening and closing the jaws.

A further object of my invention is to provide a power operated hookwhich is stable in operation and which will not become fouled or upsetwhen the hook is disengaged from the load.

A further object of my invention is to provide a power operated hookwhich may be easily adapted to operate with any type of crane or otherhoisting device.

Other objects and advantages of my invention will appear hereinafter inthe detailed description thereof in connection with the accompanyingdrawings.

In the drawings:

Figure l is a general View in side elevation of a preferred form ofdevice embodying my invention adapted to operate with a crane, andshowing the jaws in opened position.

Figure 2 is a side elevation of a preferred form of my invention, thejaws closed.

Figure 3 is a sectional view of the jaw-overlapping device taken on theline 3-3 of Figure 2.

Figure 4 is a fragmentary sectional view, taken on the line 4-4, of thecable guard and frame pivot member.

In Figure 1, a portion of a hoisting device is illustrated whereinlifting is achieved by means of a boom i, a cable 2 run through a sheave3, and block 4. The support cable 5 is suspended Means are provided forattachmg the support cable 5 to the hook unit and, as shown in Figure 1,this means may include the cable anchor yoke 6.

Pivot means connecting the jaws 7 and I are provided and, as shown inthe drawings, this means includes the pin 8, to which pin the cableanchor yoke 6 is secured.

The frame 9 is comprised of a short leg Ill and a long leg H, meansbeing provided for their pivotal connection and, as shown in thedrawings, this means includes the pin l2. The short leg l0 likewise ispivotally connected to the jaw 1 at the pin 13 which is contained by thebracket is likewise connected to the l5 which is contained by the M. Thelong leg jaw 7 at the pin bracket l6.

Cable guide means are provided and, as illustrated in the drawings, thismeans may include the two pairs of rollers H and I 8 mounted for axialrotation on the support member I 9, which is secured to the long leg ll.Rollers I! are opposed parallel members, as are rollers [8, so as toencompass the support cable 5.

Means are provided for the operable connec tion of the pneumatic powercylinder assembly to the frame 9 and jaws 'l and I and, as shown in thedrawings, includes the air cylinder 20 pivotally connected to the leg II by means of bracket 2| andL the pin 22, and the piston rod 23pivotally connected to the jaw 1' by means of bracket 24 and pin 25.

Operation of the pneumatic power cylinder assembly is effected by afour-way valve 26 mounted on a storage tank 32 and connected with thecylinder 20 by air lines 21 and 28. The four-way valve 26 is actuated bythe solenoid 29 mounted on the storage tank 32. Electric current for thesolenoid 29 is supplied through the power line 30, the switch 40preferably being located in the cab of the crane. Air line 3! suppliesair to the storage tank 32 secured to the leg I!) and which is connectedwith the valve 26 by means of air line 33.

Means are provided to prevent the opening of the jaws when subjected toa heavy load suspended therefrom. As shown in the drawings, and moreparticularly in Figure 3, this means includes the offsets 34 and 34 onthe outer ends of jaws I and l respectively so that the free end of eachjaw is received by the offset in the other. Horizontal twisting of thehook is controlled by means of the bridl 35 and bridle cable 36pivotally connected to the hook at the pin 8. Bridle stops 3'! areprovided on leg H in order to confine the vertical motion of the bridle.

As seen in Figure 2, when the piston rod 23 is retracted into thecylinder 20, the jaws are in closed or carrying position. Extension ofthe piston rod 23 causes relative separation of the pivot pins 8 and I2,bringing about through the action of legs 9 and Hi, the opening of thejaws.

A means of operating the air cylinder is illustrated in the drawings.When the solenoid 29 is energized the armature 38 is retracted and thevalve stem 39, which is secured to the armature 38, is thereby partiallywithdrawn. This allows air to flow from the supply tank 32 through airline 33, the four-way valve 26 and thence through air line 21 intocylinder 20, extending the piston rod 23, thereby causing the jaws I and'I' to open as described above.

The exhaust air passes through air line 28 to the valve 25 and is ventedfrom a port (not shown). When the electric circuit is opened and thesolenoid de-energized, the armature 38 is ejected by means of a spring(not shown), retracting the valve stem 39. This reverses the flow of airthrough air lines 21 and 28, causing the piston rod to be retracted,closing the jaws I and 1.

It will be noted that my invention provides (inter alia) for quickopening and closing of the jaws due to the arrangement of the four-wayvalve in close proximity to the air cylinder. The problem of time lagcaused by long air feed lines is obviated by use of theelectrically-operated four-way valve arrangement as described above.

While I have shown only a preferred form of my invention, it should beunderstood that various changes and modifications may be made withoutdeparting from the spirit of the invention.

I claim:

1. In a lifting hook of the cable-supported type, the combination of ajaw assembly comprising a pair of jaws and pivot means connecting thejaws, a frame comprising a pair of legs pivotally connected together,each leg being pivotally connected to one of said jaws, a cable anchoryoke connected to said pivot means, means on said yoke for anchoring thecable, a cable guide comprised of a plurality of rollers arranged toencompass the cable and positioned above the jaw assembly and said yokewhereby the jaw assembly is maintained in an upright position, apneumatic power cylinder assembly operably connected at one end 'to saidframe and at the other end to said jaw assembly, a four-way valvemechanism mounted on the frame, means for connecting the valve forcontrol of the operation of said power cylinder assembly, and means tosupply pneumatic pressure to said valve assembly.

2. In a lifting hook of the cable-supported type, the combination of apivoted jaw assembly comprising a pair of jaws and pivot meansconnecting the jaws, the outer ends of said jaws being offset so as toform an overlap between the jaws when in the closed position, a framecomprising a pair of legs pivotally connected together, each leg beingpivotally connected to one of said jaws, a cable anchor yoke connectedto said pivot means, means on said yoke for anchoring the cable, apneumatic power cylinder assembly operably connected at one end to saidframe and at the other end to said jaw assembly, a valve mechanismmounted on the frame, means for connecting the valve for control of theoperation of said power cylinder assembly, and means to supply pneumaticpressure to said valve assembly.

3. In a lifting hook of the cable-supported type, the combination of apivoted jaw assembly comprising a pair of jaws and pivot meansconnecting the jaws, the outer ends of said jaws being offset so as toform an overlap between the jaws when in the closed position, a framecomprising a pair of legs pivotally connected together, each leg beingpivotally connected to one of said jaws, a cable anchor yoke connectedto said pivot means, means on said yoke for anchoring the cable, a cableguide comprised of a plurality of rollers arranged to encompass thecable and positioned above the jaw assembly and said yoke whereby thejaw assembly is maintained in an a pneumatic power cylinder assemblyoperably connected at one end to said frame and at the other end to saidjaw assembly, a valve mechanism mounted on the frame, means forconnecting the valve for control of the operation of said power cylinderassembly, and means to supply pneumatic pressure to said valve assembly.

4. In a lifting hook of the cable-supported type, the combination of apivoted jaw assembly comprising a pair of jaws and pivot meansconnecting the jaws, the ends of said jaws being offset so as to form anoverlap between the jaws when in the closed position, a frame comprisinga pair of legs pivotally connected together, each leg being pivotallyconnected to one of said jaws, a cable anchor yoke connected to saidpivot means, means on said yoke for anchoring the cable, a cable guidecomprised of a plurality of rollers arranged to encoinpass the cable andpositioned above the jaw assembly and said yoke whereby the jaw assemblyis maintained in an upright position, a pneumatic power cylinderassembly operably connected at one end to said frame and at the otherend to said jaw assembly, a four-way valve mechanism mounted on theframe, means for connecting the valve for control of the operation ofsaid power cylinder assembly, means for actuating the four-way valvemechanism comprising a solenoid positioned in close proximity thereto,and means including a remotely extending electric cable for actuatingthe solenoid.

5. In a lifting hook of the cable-supported type, the combination of ajaw assembly compris ing a pair of jaws and pivot means connecting thejaws, the outer ends of said jaws being offset so'as to form an overlapbetween the jaws when in the closed position, a frame comprising a pairof legs pivotally connected together, each leg being pivotally connectedto one of said jaws, a cable anchor yoke connected to said pivot means,means on said yoke for anchoring the cable, a pneumatic power cylindercomprised of a cylinder member and a piston member, one of said membersbeing pivotally connected to said frame and the other member beingpivotally connected to said jaw assembly, a four-way valve mechanismmounted on the frame, means for connecting the valve for control of theoperation of said power cylinder assembly, and means to supply pneumaticpressure to said valve assembly.

6. In a lifting hook of the cable-supported type, the combination of ajaw assembly comprising a pair of jaws and pivot means connecting thejaws, the ends of said jaws being offset so as to form an overlapbetween the jaws when in the closed position, a frame comprising a pairof legs pivotally connected together, each leg be ing pivotallyconnected to one of said jaws at a position intermediate the pivot andouter end of said jaws, a cable anchor yoke connected to said pivotmeans, means on said yoke for anchoring the cable, a pneumatic powercylinder comprised of a cylinder member and a piston member, one of saidmembers being pivotally connected to said frame and the other memberbeing pivotally connected to said jaw assembly, a four-way valvemechanism mounted on the frame, means for connecting the valve forcontrol of the operation of said power cylinder assembly, and'meanstoupright position,

supply pneumatic pressure to. said valve assembly. 7

'7. In a lifting hook of the cable-supported type, the combination of ajaw assembly comprising. a. pair of jaws and pivot means connecting thejaws, a frame comprising a pair of legs pivotally connected together,each leg being pivotally connected to one of said jaws at a positionintermediate the pivot and outer ends of said jaws, a cable anchor yokeconnected to said pivot means, means on said yokes for anchoring thecable, a cable guide comprised of a plurality of rollers arranged toencompass the cable and positioned above the jaw assembly and said yokewhereby the jaw assembly is maintained in an upright position, apneumatic power clyinder assembly operably connected at one end to saidframe and at the other end to said jaw assembly, a fourway valvemechanism mounted on the frame, means for connecting the valve forcontrol of the operation of said power cylinder assembly, means foractuating the four-way valve mechanism comprising a solenoid positionedin close proximity thereto, and means including a remotely extendingelectric cable for actuating the solenoid.

8. In a lifting hook of the class described, the combination of a jawassembly comprising a pair of jaws and pivot means connecting the jaws,the outer ends of form an overlap between the jaws when in the closedposition, a frame comprising a long leg and a short leg pivotallyconnected together, each leg being pivotally connected at one of saidjaws at a position intermediate the pivot and outer ends of said jaws, acable anchor yoke connected to said pivot means, a supporting cableanchored said jaws being offset so as to in said cable anchor yoke, acable guide comprised of a plurality of rollers arranged to encompassthe said cable and positioned on the said long leg above the jawassembly whereby the jaw assembly is maintained in an upright position,a bridle operably connected to said pivot means, a pneumatic powercylinder comprised of a cylinder member and a piston member, one of saidmembers being connected to said long leg and the other member beingpivotally connected to one of said jaws intermediate the pivot and outerends thereof, a four-way valve mechanism mounted on the frame andconnected to control the operation of said power cylinder assembly,means for actuating the four-way valve mechanism comprising a solenoidpositioned in close proximity thereto, and means including a remotelyextending electric cable for actuating the solenoid.

References Cited in the file of this patent UNITED STATES PATENTS

